Alarm clock utilities for Android are a dime-a-dozen, and ultimately choosing the best one comes down to the features you need. Even so, after testing several of the more popular ones on in the Android App Market, we think that Alarm Clock XTreme is the most feature-rich and useful alarm clock available for Android, thanks to its display customization features, unique alarm settings, and more.

Features

Supports multiple alarms at different times of day in 12 or 24-hour formats

Can be configured to sound an alarm that slowly increases in volume or vibration intensity until you dismiss it or after successive snoozes

Can schedule multiple alarms, each with different songs or playlists, or to play a random song

Can be configured to require you to solve simple math problems before the alarm can be snoozed or dismissed

Can display a countdown timer on-screen until the alarm sounds, making the app useful for a timer as well as an alarm clock

Allows you to auto-dismiss or auto-snooze alarms

Allows you to customize the color and background of the alarm display

Can use GPS to automatically disable itself if it detects you're traveling without muting the alarm

Where It Excels

Alarm Clock Xtreme is a simple, feature-rich solution to what can be a complicated problem. The app's biggest strength is that it looks and feels like Android's built-in alarm and timer app, which is functional, but missing a number of the features that make Alarm Clock Xtreme and its alternatives great. By far, the "solve math to silence alarm" feature is Alarm Clock Xtreme's stand-out feature, and between that and its countdown view and home-screen widget that will never leave you wondering when the alarm is going to go off, it won us over. The fact that the app can detect when you're in motion and disable your alarm for you is a great touch as well. Aside from that, the app covers all of the bases and does it well.

Where It Falls Short

The only major drawback to Alarm Clock Xtreme is that for all of its customization and widget options, it just doesn't look at sharp as it could. The fonts are a little fuzzy and the UI looks like it was built for phones running Android 1.6 (and yet it supports 2.1 and higher) and could use a little work. Still, it doesn't have to look great to wake you up in the morning. One other minor nitpick: the ads in the free version tend to get in the way of some of the buttons at times, making it more difficult than intended to dismiss an alarm. The paid version removes the ads though, so that may be the intended solution to that minor quirk.

The Competition

Alarm Clock is Android's built-in alarm clock and timer. It goes by many names, and can be renamed and re-skinned to look however a specific ROM creator or device manufacturer chooses (for example, on my OG Droid it was called "Alarm Clock." On the Droid Bionic or Droid X, it's called "Alarm and Timer." In MIUI, it's just called "Clock." Regardless, it comes on every device, and for many people will get the job done just fine. You can set up multiple alarms, set some active and disable others, and the app doesn't have to be in the foreground for it to wake you up when the time comes.

Alarm Clock Plus (Free/$1.79 for the ad-free version) was a strong contender for the top spot (and in fact, it's the one I prefer as my daily driver) but it's missing some of the features that make Alarm Clock Xtreme great. You can tell Alarm Clock Plus to force you to do math before dismissing an alarm, and you can enable multiple alarms. You can also set Alarm Clock Plus to speak the time and/or weather aloud before the alarm goes off, so you can wake up to a voice instead of a tone or song. You can shake to snooze, or set alarms to wake you with music (although not playlists) or tell the app to open a specific application when the alarm goes off. It can also gently increase the volume of your alarm over time.

The big problem with Alarm Clock Plus is that it's buggy—never to the point where I've missed an alarm, but some users have reported it in the Android Market. It can be a little crashy, and its ads are definitely in the way of the UI. It's missing a home screen widget, and the flashlight feature that could be great is also buggy. However, if you dock your Android phone at night or on your desk and want a great desk clock, Alarm Clock Plus is a must-install app: it gives you more control over the phone's appearance when docked than Android does by default, can turn your phone into a photo frame, and gives you control over some of Android's more annoying "features" when docked. Sadly, it's just a better desk clock than it is an alarm clock. Still, it's worth a look if you want an unobtrusive alternative that can do both well.

Alarm Clock Free (Free/$0.99 for the pro version) is perfect if you like the appearance of an old school LCD clock with glowing numbers peering at you in the darkness. It also gets the job done and lets you wake to 11 selectable tones or your own songs or playlists, although it's missing extended features like math problems on wake and multiple active alarms. Still, it looks like an old alarm clock, which earns it a few points. $0.99 unlocks additional clock colors.

Alarm Droid (Free/$2.16 for the donationware version) boasts a great looking UI, multiple alarms, and the ability to snooze your phone just by flipping it over on your nightstand. It's kind of a gimmick, but aside from that the app is pretty richly featured. You can set recurring alarms by date and time and the snooze screen has multiple large buttons for different snooze durations. It doesn't do much that the other apps don't also do, but the other developers could take a page from the design of this app.

Lightning Bug (Free) is a little different. Most people use it to help fall asleep to soothing sounds of nature, but the app can just as easily be set to lull you to sleep with sounds of rain falling, monks chanting, or traffic on a city street outside your window, or wake you up with an alarm in the morning. $0.99 will buy you additional soundscapes to enjoy, like the sounds of the forest, or an ocean lapping at a tropical beach.

These are just a few of popular Android alarm clock apps. Do you have a favorite, or have an opinion about one of the ones mentioned? Let us know in the comments below.

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